From patchwork Thu Nov 17 03:56:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thadeu Lima de Souza Cascardo X-Patchwork-Id: 1704903 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=canonical.com header.i=@canonical.com header.a=rsa-sha256 header.s=20210705 header.b=fEAGekev; dkim-atps=neutral Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4NCR235lvmz23mV for ; Thu, 17 Nov 2022 14:57:15 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1ovW1V-0000UC-M0; Thu, 17 Nov 2022 03:57:09 +0000 Received: from smtp-relay-canonical-1.internal ([10.131.114.174] helo=smtp-relay-canonical-1.canonical.com) by huckleberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1ovW1M-00007n-5R for kernel-team@lists.ubuntu.com; Thu, 17 Nov 2022 03:57:00 +0000 Received: from quatroqueijos.. (unknown [179.93.206.76]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-1.canonical.com (Postfix) with ESMTPSA id 140A741DA0 for ; Thu, 17 Nov 2022 03:56:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1668657418; bh=epUy1EFx5r8zjocpDsjHqpABP7spOreMvuOnwlchgoI=; h=From:To:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=fEAGekevTceSRkP/owdb0N8BVBb8hit+f0EVAvquJLLyfXadN9GlygH64ELh0UmbC 58Hc3m9TtKxcq537+e8ZYWdyXQfpp1w9lnkeMfe+R81sEzmQarXQnvqY6ntNjTnVtp KttOCgND/WZWaiqhXYdtwvdJcUhxsB6Knnr0Tqv1SIdIRGK8AGoGP6kMvq6TQW3qtl OlB6nqYedQXv8I5s2ejOhda+/fKQg1lRf6nJBMCDN6jgFbanLFgXpySvEFvnlnubKx 0Pkq5eGfFOlWZEcMgWQ5SM9mx8bAgi4Eld5plMfOumeux9Y8AURfy401uOVybt611u 0qjDKqGJIM+OA== From: Thadeu Lima de Souza Cascardo To: kernel-team@lists.ubuntu.com Subject: [SRU Bionic 2/3] ipv6: Fix data races around sk->sk_prot. Date: Thu, 17 Nov 2022 00:56:21 -0300 Message-Id: <20221117035621.1091322-11-cascardo@canonical.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20221117035621.1091322-1-cascardo@canonical.com> References: <20221117035621.1091322-1-cascardo@canonical.com> MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Kuniyuki Iwashima Commit 086d49058cd8 ("ipv6: annotate some data-races around sk->sk_prot") fixed some data-races around sk->sk_prot but it was not enough. Some functions in inet6_(stream|dgram)_ops still access sk->sk_prot without lock_sock() or rtnl_lock(), so they need READ_ONCE() to avoid load tearing. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima Signed-off-by: Jakub Kicinski (backported from commit 364f997b5cfe1db0d63a390fe7c801fa2b3115f6) [cascardo: no pre_connect hook on inet_dgram_connect] CVE-2022-3567 Signed-off-by: Thadeu Lima de Souza Cascardo --- net/core/sock.c | 6 ++++-- net/ipv4/af_inet.c | 21 +++++++++++++++------ net/ipv6/ipv6_sockglue.c | 4 ++-- 3 files changed, 21 insertions(+), 10 deletions(-) diff --git a/net/core/sock.c b/net/core/sock.c index 5b1d63bbc431..16a9f9595662 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2973,7 +2973,8 @@ int sock_common_getsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk; - return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_getsockopt); @@ -3014,7 +3015,8 @@ int sock_common_setsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk; - return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_setsockopt); diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 5e43b0cee97e..e01369d565b4 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -530,15 +530,20 @@ int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; if (addr_len < sizeof(uaddr->sa_family)) return -EINVAL; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (uaddr->sa_family == AF_UNSPEC) - return sk->sk_prot->disconnect(sk, flags); + return prot->disconnect(sk, flags); if (!inet_sk(sk)->inet_num && inet_autobind(sk)) return -EAGAIN; - return sk->sk_prot->connect(sk, uaddr, addr_len); + return prot->connect(sk, uaddr, addr_len); } EXPORT_SYMBOL(inet_dgram_connect); @@ -693,10 +698,11 @@ EXPORT_SYMBOL(inet_stream_connect); int inet_accept(struct socket *sock, struct socket *newsock, int flags, bool kern) { - struct sock *sk1 = sock->sk; + struct sock *sk1 = sock->sk, *sk2; int err = -EINVAL; - struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + sk2 = READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern); if (!sk2) goto do_err; @@ -768,6 +774,7 @@ ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; sock_rps_record_flow(sk); @@ -776,8 +783,10 @@ ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, inet_autobind(sk)) return -EAGAIN; - if (sk->sk_prot->sendpage) - return sk->sk_prot->sendpage(sk, page, offset, size, flags); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (prot->sendpage) + return prot->sendpage(sk, page, offset, size, flags); return sock_no_sendpage(sock, page, offset, size, flags); } EXPORT_SYMBOL(inet_sendpage); diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index b433adcc0fd1..6d5fce5169fd 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -229,7 +229,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, &tcp_prot, 1); local_bh_enable(); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */ WRITE_ONCE(sk->sk_prot, &tcp_prot); icsk->icsk_af_ops = &ipv4_specific; sk->sk_socket->ops = &inet_stream_ops; @@ -245,7 +245,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, prot, 1); local_bh_enable(); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */ WRITE_ONCE(sk->sk_prot, prot); sk->sk_socket->ops = &inet_dgram_ops; sk->sk_family = PF_INET;